Railway draft spring and friction shock absorbing mechanism



, /l//gm/ G. E. DATH Filed July 22; 1944 T T-- k-n C) C) C) l l waa /i RAILWAY DRAFT SPRING AND FRICTION SHOCK ABSORBING MECHANISM I ll C. E J ,n

Aug. 1g, 1947.

If @i yPatented Aug. 1,2, 1947 RAILWAY DRAFT." SPRING AND FRICTIN SHOCK ABS'ORBING MECHANISM George E. Dath, Mokena, Ill., assigner to W. H.

Miner, Inc., Chicago, Ill., a corporation of Dela- Ware Application July 22, 1944, Serial No. 546,121

This invention relates to improvements in Shock absorbing mechanisms and more particularly to shock absorbing mechanisms employed in connection with railway draft riggings.

One object of. the invention is to provide a shock absorbing mechanism especially adapted for railway draft riggings, having combined spring and frictional resistance, wherein the shocks are absorbed by a relatively heavy spring meavns during the major portion of the compres'- sion stroke of the mechanism, followed by combined spring and frictional resistance during the remainder of the compression stroke to absorbthe heavier shocks'.

A furthe-r object of the invention is to provide in a mechanism as set forth in the preceding paragraph, means for snubbing or dampening the action of the spring means to reduce the vibratory action of the same.

A more specific object of the invention is to provide a shock absorbing mechanism of the character indicated, comprising a movable fric-V tion casing, movement of which is resisted by a relatively heavy spring to absorb the shocks during the major portion of the compression stroke of the mechanism, and a spring resisted friction clutch sldable within the casing wherein snub-r bing means is provided to snub the action of thel heavy spring, which snubbing means comprises a friction element with. respect to which the casing is movable, and spring pressed friction shoes movable with the casing and slidably embracing said friction element, and wherein high frietional resistance is produced during the latter portion of the compression stroke of the mechanism by arresting movement of the friction shell and thereby effecting relative sliding movement of the clutch and shell with respect to each other.

Other objects of the invention will more clearly appear from the description and claims hereinafter following.

In the drawing forming a part of this specification, Figure 1 is a horizontal, longitudinal sectional view of a portion of a railway draft rigging, illustrating my improvements in connection therewith. Figure 2 is a .front end elevational view of the shock absorbing mechanism illustrated in Figure 1. Figure 3 is a transverse, vertical sectional view, corresponding substantlally to the line 3 3' of Figure l, the outer spring being omitted. Figure 4 is a view, similar to Figure 1, showing the shock absorbing mechanism only, and illustrating another embodiment of the invention. Figure 5 is a top plan view of ,the mechanism illustrated in Figure 4.

f In said drawing, referring rst to the embodi- 4 Claims. (Cl. 213-24) 2 ment of the invention illustrated in Figures 1, 2, andA 3, lf2- l0 indicate channel-shaped center or draft sills of a railway car under'frame hav-ing" lowers of the railway draft rigging and the shock absorbing mechanism. The yoke is supported by a detachable saddle plate t4 secured to the` underneath sides f the sills lli-l il. Guide brackets l5-l 5 of the usual type are provided at opposite sides of the shock absorbing mechanism, the same being secured to the sills lQ-i. The front and rear followers of the draft rigging are indicated by I6' and ll, respectively.

My improved shock absorb-ing mechanism, as illustrated in Figures l, 2, and 3, comprises broadly a casing A; an outer Amain spring resistance B; a Wedge block C; three friction shoes D D-D; a spring resistance E within the casing; afriction post F; a pair of friction elements G-G; and a spring vI-I surrounding the friction elements for pressing the same against the post.

The casing A is in the form of a cylindrical tubular member which is open at its front and rear ends. At the front end, the casing Ais provided with a laterally outstanding', annular iijange lik, which acts as a springfollower member. At the rear or inner end, the casing A isprovided with an inturned stop flange l@ for a purpose hereinafter described. Between. the front and rear endsethereof, the` casing is provided with an interior, transverse partition wall 2li 'which divides the casing into front and rear chambers or compartments. The partition wall Z@ is provided with a central opening 2| therethrough which accommodates the friction post F for lengthwise movement. At the forward end of the casing, the side walls'thereof are thickened, as indicated at 22, said thickened portion of the casing forming the friction shellv proper of the mechanism. The thickened portion 22 of the casing is provided with three longitudinally extending, interior friction surfaces 2551-23-23 of V-shaped, transverse cross section. The V-shaped friction surfaces 23 converge inwardly4 of the casing, whereby a tapering friction shell section is provided. At the front end, the casing is provided with three, equally spaced, inwardly extending, retaining lugs E'll-Zfi-Z/i, which serve to limit ont-ward movement of the wedge block C`. l

The wedge C is in the form of a relatively heavy block having a vertical' dat front end face 25y adapted to bear on the main frontr follower I6. of the draft rigging. At the inner end, the block 'Y sides which slidably engage the post.

engaged in back of the lugs 24%-24-24 of theV casing to anchor the wedge to said casing.

The friction shoes D are three in number and have V-shaped, outer friction surfaces 23-28-28 engaging, respectively, the V-shaped friction surfaces 23-23-23 of the casing. VOn the inner side, each shoe is provided with a wedge face 29 which engages the corresponding wedge face 26 of the block C. The wedge faces 29-29-29 of the three shoes D-D-D are correspondingly inclined to and engaged with the three wedge faces 26-2 6,-26, respectively, of the wedge blockA C.

The spring E, which is in the form of aV helical coil, is disposed within the front chamber of the casing and has its front and rear ends bearing respectively on the inner ends of the friction shoes D-D-D and the partition wall 20 of the casing.

The spring E is preferably under initial compression in the assembled condition nism.

The friction post F is in the form of a bar of cylindrical, transverse cross section and has a disclike base portion 30 at its outer end, which is reduced in thickness at its periphery to provide an annular ange 3l, which is of lesser thickness thanY the central portion of the disc. The disc is thus, in effect, provided with a central boss, which projects forwardly and on which the friction post is located. The disclike base portion 3l) is of the same diameter 'as the peripheral flange I8 of the casing VA and functions as member. Y e Y The outer main spring VB is in the form of a relatively heavy coil which surrounds the casing A and the post F and has its front and rear ends bearing, respectively, on the flange I8 of the casof the mechaing A'and the ange 3| ofthe base portion of the post F onopposite sides and are confined againstn lengthwise movement with respect to the casing by the wall 20 and the flange I9 with which the opposite Vends of these elementsabut; The eleward each other, either by inward movement of the coupler against the front follower HiV or by pulling action of the yokeagainst the follower I1,

the shock absorbing mechanism is compressed be- Y tween the followers I6 and l'l, thereby forcing the wedge C inwardly against the friction shoes D-D-D, resisted by the spring The wedging action thus set up presses the shoes against the friction surfaces of the casing with suincient force to cause the casing toimove inwardly in unison with the wedge C against the resistance'of the`spring B. Thus, duringV the major portion of the compression stroke of the mechanism, the main resistance is offered by the spring B. While the spring B is being compressed, slightV frictional resistance is had between the friction post F and the friction elements G-G, thereby snubbing Vthe action Vof the spring B. As the mechanismris further compressed, the inner end of the casing A engages theprojecting 4boss of the disclike base portion 30 of the friction post F andY further rearward movement of the casing Y stroke.

a rear spring follower ments G fit the cylindrical post F and Vare prokvided with transversely curved, longitudinally ex` tending friction surfaces 32--32 on their inner Vof a relatively light; helical coil and surrounds the two friction elements, having its front and Vrear* ends inY wedging engagement with the wedge faces V33--33 and 33-33 ofthe two friction elements G-G. The spring H is under a predetermined amount of compression and thus constantly wedges the shoesY inwardly against the Y friction surface of the post F, due to the werdgingl engagement of the outer end coils of the Vspring with the wedge faces'33-33.

The operation of my improved shockabsorbing mechanism, as illustrated in Figures le,V 2, and 3,

On they is'asV follows: Upon Athe frontand rearfollowers Y VI E` and lx1 ofthe draft rigging being moved tois positively arrested, thereby compelling the fric@ tion clutch, comprising the shoes DK-D-D andv the wedge C to be slid inwardly of the'- friction shell during the remainderV of the compression High frictional resistance is thus provided during the final compression of the mech-a-V nism. When the actuating pressure'is reduced,

the spring B returns the casing A toY the'normalV full release position shown in Figure 1, and the r friction shoes and wedge block Care returned by the expansive action lof the spring E, outward movement of the wedge being limited by engage Yment of the lugs 21 thereof with the lugsl 24 of the Referring next terne embodiment ef the 1n-Y vention illustrated in Figures 4 and 5, the designlr is the same as that illustrated in Figures 1, 2,',andA` 3, with the exception that the friction elements,

which cooperate with the post, are anchored'toj the rear end of the casing instead of being con-v fined within a chamber of the casing, and thatV Vthe friction' post is in the instead of a cylindrical bar.

My improved shock absorbing mechanism, Yasv illustrated in Figures 4 and 5, comprises a'ca'sing"- K; twov friction shoes L-L; a frictionY post'M with which the shoes cooperate;Y and the follovgf#` ing additional parts which are al1 identical with' tional spring H.

The casing K is inthe form ofaY cylindrical,

tubular member, Vclosed at its rear end by 'a'rtransf verse, vertical wallr'having a transverseopenw ing't therethrough, adapted to accommodate the platelike friction post M for lengthwise.move-.Y Vment.V At the rear end, the'cas'ingK has .Y an" Youtwardly projecting, relativelyv heavylugj,`

which is in the form of a dovetail projection.'L e At the front end, the'casing K is provided with f an annular, outstanding flange H78, ysimilarfto the flangeV i3 hereinbefore described. AAt -theV front VVend of Vthe casing, three interior frioltion surfaces 92,3 623-423 are I'Jrovided"wl'iichiV correspondgto the frictionlsurfaces 23,-f'123--e23fY Y hereinbefore described, and which are Aofi/415 shaped, transverse cross section and cooperate with the corresponding y-syhapedefriction surfaces -Y of the shoes AD-D-D..."V` ThecasingwK is alsoPIQf form of a flat plate;

vided with three interior lugs l24-l24-l24 at the front end thereof, which correspond to the lugs 24-24--24 hereinbefore described and serve to anchor the wedge C' to the casing.

The post M comprises a flat, platelike section having longitudinally disposed, flat friction surfaces l34-l3ll on opposite sides thereof. The platelike post M is provided with a disclike base |39 having an annular ange ISI, corresponding to the disclike base 30 of the post F hereinbefore `described and the flange 3l of said disc.

The friction elements L are in the form of elongated blocks having flat friction surfaces |35-l35 on the inner sides thereof engaging the fiat friction surfaces |34-l34 at opposite sides of the post M. At the front and rear ends, the shoes are provided with wedge faces 13S-36 which face inwardly and function in the same manner as the wedge faces 33-33 of the friction elements G hereinbefore described. The spring H, which is similar to the spring H hereinbefre described in connection with Figures 1, 2, and 3, is under a predetermined compression and has wedging engagement with the wedge faces |35- |36 and 13S-|36 of the friction elements L-L to force the latter against the friction post. Each shoe is provided with a forward extension 31 having an opening 38 of dovetail form adapted to receive the corresponding dovetail portion of the lug 36 of the casing K. The friction elements L-L are thus anchored to the casing K by the dovetail connection, andwhile they are compelled to move in unison with the casing in lengthwise direction, they may move laterally inwardly and outwardly to properly cooperate with the friction post, that is, so that they may be wedged against the post by the action of the spring I-I.

The operation of the mechanism illustrated in Figures 4 and 5 does not materially differ from the operation of the mechanism hereinbefore described in connection with Figures 1, 2, and 3, and therefore no further detailed description thereof is required.

I have herein shown and described what I now consider the preferred manner of carrying out my invention, but the same is merely illustrative and I contemplate all changes and modifications that come within the .scope of the claims appended hereto.

I claim:

1. In a shock absorbing mechanism, the combination with a friction casing having a spring follower flange at its outer end; of a friction post having a spring follower flange at its outer end, said casing and post being movable in lengthwise direction toward and away from each other; a main spring resistance interposed between said follower flanges of the casing and post and yieldingly opposing relative lengthwise movement of the casing and post toward each other; cooperating stop means on said post and casing limiting relative lengthwise movement of the casing and post to less than the full cornpression stroke of the mechanism; friction shoes within the `casing embracing the friction post and having sliding engagement therewith; stop shoulders on the casing engaging said shoes to hold said shoes against movement lengthwise of the casing; means for yieldingly pressing said shoes against the post; and a spring resisted friction clutch slidingly telescoped within the casing and receiving the actuating force.

2. In a shock absorbing mechanism, the combination with a friction casing; 0f a friction post, said casing and post being movable in lengthwise direction with respect to each other; a main spring resistance yieldingly opposing relative lengthwise movement of the casing and post; stop means on said post engageable with the inner end of the casing to limit relative lengthwise movement of the post and casing to less than the full compression stroke of the mechanism; friction shoes within the casing at the inner end thereof; shoulders on said casing engaging the opposite ends of said shoes to hold said shoes against movement lengthwise with respect to the casing, said shoes embracing said post and having lengthwise sliding engagement therewith; means for yieldingly pressing said shoes against the post; and a spring resisted friction clutch slidingly telescoped within the casing and receiving the actuating force.

3. In a shock absorbing mechanism, the combination with a friction casing; of a friction post, said casing and post being movable in lengthwise direction with respect to each other; a main spring resistance yieldingly opposing relative lengthwise movement of the casing and post; stop means on said post limiting relative lengthwise movement of the post and casing to less than the full compression stroke of the mechanism; dovetail anchoring lugs projecting from the inner end of the casing; friction shoes having dovetail seats receiving said lugs for anchoring the shoes to the casing for movement in unison therewith, said shoes embracing said post and having lengthwise sliding engagement therewith; means for yieldingly pressing said shoes against the post; and a spring resisted friction clutch slidingly telescoped within the casing and receiving the actuating force,

4. In a shock absorbing mechanism, the combination with a friction casing; of a friction post, said casing and post being relatively movable toward and away from each other in lengthwise direction; a follower flange at the outer end of the casing, said casing being open at the outer and inner ends; an inturned stop flange at the inner end of the casing; an interior, transverse partition wall between the ends of the casing; friction elements confined against endwise movement with respect to the casing between said partition wall and inturned stop flange, said elements embracing the post therebetween and having lengthwise sliding engagement therewith; spring means within the casing forcing said elements against the post; an abutment on said post engageable with the inner end of the casing to limit relative lengthwise movement of the casing and post to less than the full compression stroke of the mechanism; friction shoes having lengthwise sliding engagement with the interior walls of the casing at the outer end portion of said casing; a wedge block receiving the actuating force and having wedging engagement with the shoes; and additional spring means within the casing interposed between said partition wall and shoes and yieldingly opposing inward movement of the shoes.

GEORGE E. DATH.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,288,661 OConnor Dec. 24, 1918 1,844,234 Wildin Feb. 9, 1932 2,398,083 Dfth Apr. 9, 1946 

